/Engine/Plugins/Experimental/GeometryScripting/Source/GeometryScriptingCore/Public/GeometryScript/PolygonFunctions.h
Returns the number of vertices in a Polygon's outer shape, if HoleIndex is -1, or in the specified inner hole. Returns 0 for invalid Polygon or Hole indices.
[UFUNCTION](Programming/UnrealArchitecture/Reference/Functions)(BlueprintCallable, Category="GeometryScript|PolygonList", Meta=(ScriptMethod)) static int32 GetPolygonVertexCount ( [FGeometryScriptGeneralPolygonList](API\Plugins\GeometryScriptingCore\GeometryScript\FGeometryScriptG-) PolygonList, bool & bValidIndices, int32 PolygonIndex, int32 HoleIndex )